(1) Field of the Invention
This invention relates generally to an apparatus for facilitating measurement of the hovering ability of a countermeasure device, and more particularly to an apparatus for retaining a countermeasure device in a vertical guide path to enable testing of the hovering and depth control capabilities of the countermeasure device.
(2) Description of the Prior Art
The use of acoustic countermeasure devices in undersea warfare is common throughout the world. Some of these devices are required to hover in place, and therefore utilize a propeller and motor system to enable the countermeasure device to hover. During the design of these countermeasure devices, the hovering ability must be tested in order to determine the performance of the system. When testing the hovering capabilities of the countermeasure device, it is important that the countermeasure device only be allowed to travel in a vertical plane in order to eliminate any horizontal movement which may interfere with the testing of the countermeasure device.
Furthermore, conventional testing of the hovering capabilities of countermeasure devices requires that the testing be done in large water tanks which can accommodate the size of the entire countermeasure device.
What is needed therefore, is an apparatus for testing the hovering ability of countermeasure devices, which provides a vertical guide path for the countermeasure device for restricting travel of the countermeasure device in a vertical plane. Such an apparatus would enable convenient and accurate testing of hovering countermeasure devices and would reduce the size of the tank in which the tests are conducted.
Accordingly, it is an object of the present invention to provide an apparatus which is capable of restricting the travel of a hovering countermeasure device in a vertical path to enable the hovering ability of the countermeasure device to be tested.
It is a further object of the invention to reduce the volume of water necessary for performing hovering tests of countermeasure devices.
The present invention is directed to a test fixture for testing hovering performance of a countermeasure device tailcone. The tailcone includes a motor and a propeller which is driven by the motor. The test fixture has an upper support device, a lower support device, at least one cable connected between the upper and lower support devices and a connection device which slidably attaches the tailcone to at least one cable. The fixture thereby restricts movement of the tailcone along the at least one cable. The upper support device is supported above a water-filled tank, the lower support is disposed in the water-filled tank and the hovering capability of the tailcone is tested by operating the tailcone in the tank. The connection device includes a number of extensions affixed to the tailcone. The number of extensions each include a clasp spaced from the tailcone, wherein the cables are threaded through the clasps, thereby attaching the tailcone to the cables. The fixture further includes a winch attached to the upper support device, wherein one of the cables is wound onto the winch, the winch being operative for taking up the cable attached thereto, thereby pulling the lower support device from the tank.